1. Field of the Invention
The present invention relates to a method for forming an imprint pattern.
2. Description of the Related Art
With the development of the miniaturization of silicon semiconductor pattern, in the case where the patterning is conducted by using a photolithography apparatus, there are some problems in view of the requirement of the high accuracy and the like for the photolithography apparatus. Namely, the photolithography apparatus becomes expensive by itself and the processing cost for the silicon semiconductor pattern also becomes expensive so that the miniaturization cost for the silicon semiconductor pattern becomes expensive. Recently, therefore, an alternative technique to be substituted for the photolithography technique is desired as the silicon semiconductor patterning technique.
Recently, an attention is paid to an imprint method as introduced in References 1 and 2 where an original plate (template) with a pattern to be transferred is pressed against a photo-curable organic material layer (resist layer) coated on a substrate and then, the thus patterned resist layer is cured by means of light irradiation or thermal treatment so that the intended pattern is transferred and formed for the resist layer.
The imprint method can form a minute structure and is a patterning method of low cost. In the imprint method, however, since the template is directly contacted with the substrate to be treated, if the template is used repeatedly, some foreign matters may adhered on the template and the debris originated from the resist layer may stopped up into the trenches of the pattern of the template. In this point of view, in the following imprinting process, the common defects may be created originated from the foreign matters and the like, which is a problem for conducting the pattern formation for the substrate using the imprint method.
Therefore, after the template for the imprint method is used at a prescribed number of times, the template is required to be substituted with an alternative template. However, it is difficult to determine the timing in substitution of the template. If the substitution frequency of the template is set more, the throughput of the imprinting process may be deteriorated and the cost of the imprinting process may be increased because a large number of templates must be prepared. On the contrary, if the substitution frequency of the template is set less, the defects as described above may be created so that the yield ratio of the pattern formation for substrates to be treated may be deteriorated.    [Reference 1] JP-A 2001-68411 (KOKAI)    [Reference 2] JP-A 2000-194142 (KOKAI)